Method and apparatus for coating fabrics



R. s. ALLEN METHOD AND- APPARATUS FOR COATING FABRICS April 24, 1928.

A '2 Sheets-Sheet 1 Filed Nov. 9, 1921' I iwerdvm' April 24, 1928. I 1,667,408

R.- S. ALLEN METHOD AND APPARATUS FOR COATING FABRICS Filed Nov 9. 1921 2 hees-$heei 2 -/-v-m RALPH s. 4 1 fM Aim/9N5 Y Patented Apr; 1928. I

RALPH S.

ALLEN, OF N NEW JERSEY, ASSIGN 03.1

numm CORPORATION, 1

OF'NEWARK,=NEW JERSEY, .A OOBPOBTION OF NEW JERSEY.

METHOD AND APPARATUS COATING FABRICS.

Application filed November 8, 1981. Serial ll'o. 518,900.

The present invention relates to coated fabrics and more particularly to a process and apparatus for applying coating compositi'ons to fabrics. 5 In certain of the coated fabrics heretofore used the coating composition has been a plied directly to the surface of a suitab e fabric-basewithout penetrating or saturating the warp and Weft of the fabric. The penetration and'saturation of the fabric base are avoided. because they tend to render the coated fabric stifi' and inflexible and therefore unsuitable for the purposes to which coated fabrics are: usuall applied. In 1 coated fabrics formed in this manner the coating is; held on the surface of the fabric principally by, the adhesive strength. between the coatin "face no su stantial anchorage of the coating 90 in the fabric base being obtained owing to the difficulty of obtaining an anchorage without saturatin the fabric'base. The coating of coated. fa ricsof this character is therefore very weakly attached and has a strong tend- 28 ene to peel from the fabric base if the fabric be nt or creased. Such fabrics are there! forefnot satisfactory for use as substitutes fornatural leathei' or-other uses for which a flexible, durable fabric is required. 30 An object ofthe present invention is to rovide a coated fabric in which the coating is tenaciouslv and flexibly anchored to the body of the fabric has.

Another object of the invention is to provide a coated fabricin which asubstantial anchorage of the coating of the fabric base is obtained by means of anchoring portions of the coating composition extending from the under surface of the coating into the 40 body of the fabric.

A still further object of the invention is to provide. a flexible coated fabric having a number of anchoring rojections'extending from the coating into the body of the fabric.

1 5 .A further object of the present invention is to provide a method of coating fabrics in which a portion of the coating composition is drawn into the fabric base in such a manner as to form a number of anchorages con- 7 so 'necting the coating to the body of the fabric base. a

A still further objectof the invention is to provide a method of coating fabrics in which a tenacious uniform anchorage of the coating to the fabric base may be obtained.

' Fig. 1 is a sectional elevation of a coating and fabric at their contact surdrawing a 'ortion of the coatin A still further object of the invention is to provide an apparatus for coating fabrics by which a uniform and thorough anchorage of the coating in the fabric base may be o'tained without soaking or saturating the fabric base.

With these and other objects in view, the mvention'comprises the method and apparatus described in the following specification.

The various features of the invention are illustrated in the accompanying drawings in which,

device embodying a preferred form of the. invention v Fig. 2 1s a sectionalfelevation of modified form of coatin apparatus,

Fig. 3 is an e evation of a part of the coatingapparatus shown in Fig. 2 taken at right an les to the section of Fig. 2, 4

ig. 4 is a cross section of a coated fabric showing in a diagrammatic manner a conventional embodiment of the invention,

'5 is a cross section on a greatly magscale of the invention as a plied to the common type of fabric base, and? 6 is a cross section on a greatly magnifie scale of a coated fabric embodying a form' of the invention as applied to a fabric base havingza nap on the surface to which the'co'ating is applied.

In the present invention the coating is attached or anchored to the fabric base by composition into the fa ric base to a sufficient extent to. fill or partly fill the crevices and channels which may exist or may be formed in the' body of the fabric base. In forming the coated fabric the coating composition is applied to one face of the fabric'and ;a slight suction is ap lied to the o posite face of the fabric direct y opposite the a plication of the coatingsuflicient to with raw the air from the pores or channels of the fabric and mo draw thereinto a portion of the coating composition which thereupon fills or partly fills the crevice and channels and serves as an anchorage to attach the coating to the fabric base. To this end. the fabric to be coated 106 is drawn, under suitable'te'nsion, beneath a side of the-fabric.

Immediately beneath the feed trou h is positioned a suction or vacuum cham r' having a slot or opening in its top wall immediately beneath the slot of the feed trough. One side of the feed trough is preferably extended to such a distance, in relation to the vacuum chamber, as'. to form a doctor blade serving to regulate the thickenss of the coating. the feed trough and the vacuum chamber a layer of coating composition is applied to the nap and is immediately drawn into the fabric by the suction applied to the .opposite 'The width of the slot in'the vacuum chamber is of such a dimension as not to extend beyond the doctor blade and, as the fabric passes under the doctor blade, the effect of the vacuum therefore ends and any further tendency of the composition to saturate the fabric base is thereby avoided.

The fabric is thereupon able drying orI hardening chamber in which the coating is hardened or dried. If several coatings are to be applied, the fabric may be passed beneath a number of feed troughs or successively beneath a single trough. In

drawn into a suitthis case the suction or vacuum is used only in connection with the earlier coating which penetrates into the fabric, the final coatings serving primarily to form a hard or nished surface on the softer body of the coating . Any fabric suit-able for use as a base for coated fabrics and having a sufficiently open or porous texture to permit the coating composition to be drawn thereinto may be employed. A fabric base having a nap or pile raised on the side to be coated may be employed or a woven fabric having a felted or partly felted structure may also be employed. The degree of vacuum and the duration of its time of application are so adjusted as to permit the formation of an anchorage without completely saturating or penerating the fabric base.

Referring more particularly to the accompanying drawings, a sheet of fabric 10 is drawn from a suitable roll or source of supply, not shown, around a tension roll 12 and idler-or positioning rolls 14-. and 16 and is assed beneath a composition feed trough 18, 1n such a manner that the face to be coated is uppermost as the fabric passes under the trough. The feed trough 18 is preferably formed of two sides, 20 and 22, which converge to a narrow slot 24 at their lower end. Positioned immediately beneath the feed trough 18 is a vacuum chamber, 26, which is connected by a connecting pipe 28 with a for produc- The upsuitable, suction device or means ing a partial vacuum, not shown. per surface of the suction or her 26 is provided with a longitudinal slot 30,.which is directly beneath the slot 24 of As the fabric passes between vacuum chain-- 26and the lower edge serves as a doctor blade to regulate the thickness of the coating applied to the fabric. In Figs. 4, 5 and 6 of drawings, the thickness of the coating composition above the fabric is relatively thin as compared with the. total thickness of the fabric. As the fabric passes over the slot 30 the air contained in the upper portion of the fabric is drawn downwardlv out of the fabric and the coating composition is thereby permitted to sink into the channels or openings of the fabric base from which the air has been withdrawn. The vacuum or suction through the slot 30 is so regulated as to avoid drawing the coating entirely throu h and saturating the fabric base. As the fa ric passes under the doctor blade 22, it moves out of contact with the suction chamber 26 and any tendency toward a further, slow penetration or soaking of the fabric base is thereby avoided. The fabric is thereupon drawn over an idler or positioning roller 32 to a suitable drying or hardening chamber, not shown. When the coating .is sufficiently dried or hardened the stiffness forming certain kinds be lessened or removed fabric in somewhat the leather is rendered more fabric the main portion of the coating will lie over, and contact with, the upper surface of the fabric base in the usual manner, as shown in Fig. 5 of the drawings, and a number of projections 33 will extend downwardly under the woof threads 35 or vice versa and will partly or very nearly encircle and.

grasp portions of the threads.

The invention may also be applied to a fabric having a pile or nap formed on the surface to be coated. This pile or nap is preferably short or shortened to give an upstanding character to the threads of the pile or nap and permit penetration by the coating composition. The coating composition is accordingly drawn downwardly through the nap or pile into the hollows and depressions formed in the upper surface of the fabric base,'as shown, for example, in Fig. 6. It will be understood that any suitable coating lld composition may be employed but for the manufacture ofart-ificial leather a cellulosic composition such as the usual composition of pyroxylin and castor oil withsuitable sol-v vent or any other suitable solution of cellulose is employed. The portion of the coating composition extending into the fabric base is preferably somewhat softer and more flexible than the surface of the coating and contains a larger proportion of castor oil in order to give the fabric the desired flexibil ity. A harder surface coating having a higher percentage of proxylin is finally applied to the surface of the coating to give greater wearing qualities and a better finish.

In the form of the invention shown in Fig. l the fabric is, drawn taut over the suction chamber 26, the regulation of the thickness of the coating being'obtained by the distance between the doctor blade 22 and. the upper surface of the suction chamber. In the modification shown in Figs. 2 and 3, the fabric is drawn tightly upwardly under the doctor having downwardly blade 22. V

Means are also provided in the modification shown in Fig. 2 for swinging the suction chamber 26 out of position to permit the application ofsucceeding coatings, for which the use of suction is not required. For this purpose a rotatable or swinging connection 54 is provided between the pipe 28 and the suction chamber 26, and the chamber 26 is connected to the rotatable connection by means of a short pi e 36. Through this arrangement the suction chamber may be 0- sitioned in operative relation to the feed trough as shown in full lines or out of position as indicated in dotted lines in the drawings. The chamber 26 and pipe 36 are secured in operative or inoperative position by means of a tightenin bolt 38.

In the embodiment 0 the invention illustrated in Fig. 1, means are provided for raising the vacuum chamber 26 and adjusting its position relative to the trough 18 and doctor blade 22 and thereby controlling the thickness of the coatings. To thisend, the vacuum, chamber 26 is carried on a frame '37 extending projections or arms 39 which areclamped against corresponding uprights 29 by means of bolts 40 passing through vertical slots 42 in the uprights 29. By moving thebolts upwardly or downwardly, the position of the vacuum chamber 26 may be changed to adjust the thickness of the coating applied to the fabric. The suction pipe 28 is also adjustably connected to the chamber 26 by meansof a pipe 44, which telescopes into a larger pipe 46 connected to the suction pipe 28 and fixed in position by means of a set screw 48.

By means of the above invention a tenacious and flexible anchorage may be cheaply and easily provided between the fabric base and the coating applied thereto. It will'be short projecting fibres,

.com osition feeding means and apparent that various types of coating compositions may be em loyed and that other methods of forming the described in detail above may be employed without departing of the invention.

Having described the invention what is claimed as new is: i

1. A method of forming coated fabrics,

which comprises applying a coating composition to the nap of a napped fabric and drawing said composition into said nap by suction appliedto the opposite side of said fabric.

2,-A method of forming coated fabrics, which comprises forming a fabric having a surface of fibres extending outwardly from the face of the fabric for a. comparatively short distance, applying suction to a limited portion of. the face of said fabric opposite said projecting fibres and a plying a coatin composition to the fibrous ace opposite said portion.

3. A method of forming coated fabrics which comprises applying a coating composition to the fibrous face of a fabric having applying suflicient suction to the opposite face of said fabric to draw said composition to the ground of said fabric and immediately thereafter relievin said suction.

4. l method of forming coated fabrics which comprises passing a fabric having fibres extending transversely of said fabric over a slot in such a manner as to expose said fibres, applying a coating composition to from the broader features anchorage than that i said nap directly opposite said slot, withdrawin air from said fabric through said slot and thereupon reducing said coating to a uniform thickness by'the application of a'pressure plate.

5. A method of coating fabrics having a short nap which comprises, applying a coating composition to said 'nap and withdrawing air through. said fabric from said nap immediately beneath said composition until said composition has been drawn into said nap for a substantial distance.

6. A method of coating napped fabrics which comprises applyin a coating composition to the nap of sai drawing air through said fabric from the nap immediately beneath said composition until said composition has been drawn into said nap a substantial distance, while avoid ing drawing said composition through said fa ric.

7. An apparatus for coating fabrics which comprises a suction chamber, a slot in said suction chamber. a composition feeding means above said slot, means for drawin said fabric over said slot and beneath sai a doctor bla e arranged immediately back of said composition feeding means.

8. Anapparatus for coating fabrics which position feeding trough above said slot, a 25 comprises a long suction chamber, axslot in doctor blade adjacent trough, means for the upper part of said' chamber, a composidrawing a fabric between said trough and tion feeding trough above said slot and a said feed slot and means for changing the v doctor blade adjacent said trough. position of said chamber relative to said feed 9. An apparatus for coating fabrics which trough and saiddocto'r'blade. comprises a long suction chamber, a slot in 12. A method of forming coated fabrics the upper wall of said chamber a feed trough which comprises applying a coating 'comabove said slot, a doctor blade adjacent said position toone face of a fabric base, drawtrough and means for drawing a fabric bemg said composition into depressions and tween said trough and slot transversely of openings in said fabric base without drawing said slot and under said doctor blade. said'composition to the opposite side of'said 10 An apparatus for coating fabrics, which fabric, drying said coated fabric and there comprises a suction chamber, a slot in the after'working said fabric to render it sufli- 15 upper wall of said chamber, a composition cicntly flexible.

feeding trough above said slot, a doctor blade 13. A method of forming a coated fabric 40 adjacentsaid trough and means for drawing which comprises applying a coating to a a fabric between said trough and said slot fabric drawing said coating into the opentransversely of said slot and a tension r011 ings in said fabric while avoiding the imarranged to maintain said fabric under tenpregnation of the threads of said fabric,

' Y sion. drying said coating and working said coated 11. An apparatus for coating fabrics fabric until sufficiently flexible. which comprises, a suction chamber, a slot In testimony whereof, I afiix my signature. in the upper wall of chamber, a com- RALPH S; ALLEN. 

